The present invention relates to a tie gun for wrapping and fixing a tape loop around a bundle of elongated articles and, more particularly, to a tie gun with which tape stock is removed from a formed loop in manner as leaves no more than innocuous tape material tab residue.
Various constructions of tie guns and like devices for tying bundles of elongated articles in a compact array thereof are known. Widely practiced uses of these devices is for tying electrical wire bundles in vehicles and environments where it is sought to restrain the wires from contact with chafing surfaces on environment structure, to hold them in manner as precludes their presenting obstruction to tools and workers performing tasks about the wires etc.
Representative of such tie guns and devices are U.S. Pat. Nos. 3,391,440; 4,094,342; 4,178,973; 4,263,687; 4,368,762; 4,371,010; 4,502,905; 4,534,817 and 4,610,067.
In known tie gun constructions, it is common that severance of the tape in a tied loop from a stock run is effected with a cutter such as a knife element. A disadvantage of such manner of severing a welded loop from the stock run is the leaving of a tab at the weld which tab, and due to the material nature and small thickness of the tape, presents an objectionable protuberance that can cause injury to a worker's fingers. It also may be an obstruction on which a tool being used by a worker in a confined space where the tie is located in end use purpose can become caught. Also where a tab in a tied loop exists, the same came represents an agency by which undesired peel of the loop securement might be deliberately or accidentally effected.
A known construction of tie gun uses a micro wave generator for effecting welding of the loop. After welding, a cutting wire located proximal the area of tape weldment is resistance heated to cause melting across the tape stock and consequent severing of the tape stock from the welded loop. While the residue of melted tape on the loop at point of severance is less than where mechanical cutting is used, there is still some tab like presence that would better be eliminated.
Known constructions in some instances feed tape from the stock to loop forming locations in a way that misfeed of tape results in undesirable and hard to remove tape pile up in the device sometimes necessitating some disassembly of gun components to effect tape release and clearance.
Additionally, some constructions are susceptible to tape leading end slippage when a loop is tightened around an article bundle before welding is carried out resulting in failure to achieve a permanent loop hold around the articles. To prevent against this requires very high clamping pressure applied against the tape leading end where same is overlapped with loop closing length of the tape stock.
It is desirable therefore that an improved tie gun construction be provided to overcome these as well as other disadvantages present in known types of constructions.